Keith Urban and Nicole Kidman celebrated their eighth wedding anniversary on Wednesday (June 25), and although the country superstar had a concert in Melbourne, he made sure that his gorgeous wife got some love from the stage.

Urrban dedicated a song written about Kidman to the actress, who was in the audience. He also gave his crowd -- and us -- a peak into how their relationship developed. A fan yelled out "Happy anniversary!" and that was all he needed to delve into one of the sweetest stories ever told on a country music stage.

"It is tonight," Urban told the crowd in between cheers. "My wife and I are celebrating eight years of marriage tonight. And she's here tonight."

"This is a true story; it happened eight years ago. Eight years and change," the singer said with a laugh. "Nic and I had just gotten engaged in September of '05. And we were planning our wedding, which was going to take place here in Australia, in June."

"A couple months or so before our wedding, we were in our hotel and we were talking about the future and I could tell that Nic was getting very nervous about the thought of marrying me," he added, chuckling.

He showed nothing but empathy for Kidman and her nerves, explaining to the fans: "It's a big thing you know? It's a big thing to get married. It takes an enormous amount of trust and a leap of faith ..."

The 'Cop Car' hitmaker was trying to find any way to reassure her that he was going to be "her man, forever," noting, "You guys know it's hard in the moment because you don't have the future yet -- you can feel it inside of you, but you just wish to God that you could bring your entire life into this room, into this moment, and show them, 'This is forever.'"

That's where country music came into the picture. The next day, as Urban thought about his future wife's fears, he met with a songwriter friend -- without the intention of writing a song about everything Kidman and Urban were going through. But a song came out anyway.

And in 2014, he introduced it to concertgoers before dedicating it to his wife. "This is called 'Once in a Lifetime,'" he started. "Eight years, baby girl, this is for you tonight my love; I love you so much."

Urban has said that his life started when he met his red-haired beauty, and she returns his devotion, calling him her "great love."